Triple valve device



Teb. 25, 1936.

J. c. MCCUNE TRIPLE VALVE DEVICE Filed May 29, 1931 2 Sheets-Sheet 1 /05 llle /lo 121 -l3l /ao la@ 77l 126 a4 [23 IN VENT 0R.

JOSEPH CMC CUNE @wf/w ATTORNEY.

Feb. 25, 1936. J. c. MccUNE TRIPLE VALVE DEVICE Filed May 29, 1951 2 Shees--Sheerl 2 E N Om. Rw Y. E mm M .0 WMZ .JWM n.0 .S .0.9 O .VI J. lo

Patented Feb. 25, 1936 UNITED STATES TRIPLE VALVE DEVICE Joseph C. McCune, Edgewood, Pa., assignor to The Westinghouse Air Brake Company, Wilmerding, Pa., a corporation of Pennsylvania Application May 29, 1931, Serial No. 540,860

38 Claims.

This invention relates to uid pressure brakes, and more particularly to a brake equipment of the type employing a brake pipe and a fluid pressure supply pipe independent of the brake pipe.

It has heretofore been proposed to provide a brake equipment of the above type and one object of my invention is to provide an improved brake controlling valve device for such an equipment.

Another object of my invention is to provide an improved brake controlling valve device having an equalizing valve device which functions as a pilot valve device in controlling the application and the release of the brakes.

Another object of my invention is to provide an improved brake controlling valve device having an equalizing valve device for controlling the application and release of brakes, and release ensuring means for effecting positive movement of said equalizing valve device to the release position when the brake pipe is charged to substantially the pressure normally carried.

Another object of my invention is to provide an improved brake controlling valve device for controlling the application and release of brakes and movable to release position upon a small increase in brake pipe pressure after an emergency application of the brakes.

Another object of'my invention is to provide an improved brake controlling valve device having a choke for controlling the rate of supply oi uid under pressure to the brake cylinder in a serive application of the brakes and an emergency valve for opening a by-pass around said choke for increasing the rate of supply of 35 uid under pressure to the brake cylinder in an emergency application of the brakes.

Another object of my invention is to provide an improved brake controlling valve device having a quick service position for venting fluid under pressure from the brake pipe to a quick service chamber, and a service position for venting fluid under pressure from the brake pipe directly to the atmosphere, and for at the same time controlling an application of the brakes. 45 Another object of my invention is to provide an improved brake controlling valve device having an equalizing valve device for controlling the supply of uid under pressure to the brake cylinder, and means operated independently of said 50 equalizing valve device for varying the rate at which fluid under pressure is supplied to said brake cylinder.

Other objects and advantages will appear in the following more detailed description of my invention.

In the accompanying drawings: Fig. 1 is a diagrammatic view of a uid pressure brake equipment embodying my improvements; Fig. 2 is a diagrammatic sectional view of the brake controlling valve mechanism shown in Fig. 1 and with the parts in their brakes released position; Fig. 3 is a diagrammatic view of the equalizing portion of the brake controlling valve mechanism shown in Fig. 2 with the parts shown in service application position; Fig. 4 is a diagrammatic view of the equalizing portion of the brake controlling valve mechanism shown in Fig. 2 with the various parts in emergency application position; Fig. 5 is a diagrammatic view of the equalizing portion of the brake controlling valve mechanism shown in Fig. 2 with the various parts shown in graduated release position; Fig. 6 is a sectional view of a'fragment of the brake controlling valve mechanism shown in Fig. 2, showing the application control plug valve in a. different position; and Fig. 7 is a sectional view of the cutout valve shown in Fig. 1 with the plug valve in a different position.

As shown in Fig. 1 of the drawings, the improved uid pressure brake equipment comprises a brake controlling valve mechanism I, a uid pressure supply reservoir 2, a brake cylinder 3, a brake pipe 4, a uid pressure supply pipe 5, a cutout valve device 5 and a check valve device 1.

The brake controlling valve mechanism comprises an equalizing valve device 8, a service application valve device 9, a service application valve control valve I0, a release valve device II, a release ensuring valve device I2, an emergency application valve device I3 and a vent valve device I4.

The equalizing valve device 8 comprises a piston I5 having at one side a chamber I8 communieating through passage I'l with the brake pipe 4, and having at the other side a valve chamber I9 communicating through a passage 20 with a pressure or control chamber 2|. The piston I5 is provided with a stem 24 extending through chamber I9, said stem and p iston being adapted to move a main slide valve 22 and an auxiliary slide valve 23 to various positions in accordance with variations in pressure on the opposite sides of said piston.

A graduated release stop device is provided for limiting the movement of the equalizing piston I5 and slide valves 22 and 23 in graduating the release of brakes and comprises a valve piston 25 having a chamber 26 at one side and open at the other side to the valve chamber I9. Said valve piston is provided with a stop 2l preferably extending mw the vslve'cnmber n and adapted under` certain cenditionsfto be engaged by the piston stem 24, but the valve piston is normally maintained in the position shown ln the draw- 5 ings bye spring 28. Inthis normal position, the stop 21 is out-of engagement wlth piston stem 24. and saisi valve piston engages a seat 29.

Extending into the equalizing piston chamber 36 and 31. The check valve 36 contained in a chamber 38 and the check valve 31 is contained in a chamber 39. Each of said eheck valves has a iiuted stem extending into and engaging one another in a chamber 49 -which is open through passage 4| to the service application valve piston chamber 33. Fon moving the check valves in one direction, a flexible diaphragm 42 is provided. 'I'he diaphragm 42 has at one side a chamber 43 and is open at the other side to chamber 39. and a follower 44 interposed between said diaphragm and the'check valve 31. A spring 45 in v the check valve chamber 38 is provided for urging the valves 3e and 31 in the opposite direction so as te seat valve 38 and unseat valve 31.

The release valve device comprises a pis=Y ton 46 having at one side a chamber 441 containing a spring 48 acting on said piston and hav ing at the opposite side a chamber 48 containing a slide valve 50 adapted to be operated by piston.

The release ensuring valve device I2 comprises 0 a piston 5| having at one side a chamber 52 and at the opposite side a chamber 53, and a poppet valve 54 contained in a chamber 65 and adapted to be unseated by said piston. 'I'he piston 8! and valve 54 are connected together by a iluted 5 stem 56, and a spring 51 is provided in chamber 55 for urging the valve 54 into engagement with a seat rib V58.

For controlling the operation of the piston 5|,

a valve 59 is provided in a chamber 60 and is o adapted to be pressed into engagement with its seat by the deilection ci a exible diaphragm 8| having one side open to chamber 60 and the opposite side open to a chamber 62. The valve 59 is provided-with a uted stem extending into 55 a chamber 63 and carrying a spring seat 64 acted upon by a spring 65. The other end of spring is supported in a spring seat 66 adjustably mounted on-a screw-threaded stud 61, one end of which is secured to the casing. It will therefore be evi- .e dentl that spring 65 may be adjusted by varying the position of seat 66 on stud 61, so that regardless of possible variations in manufacture, each and every release ensuring valve device i2 may be adjusted to the same spring pressure,

05 to thereby provide imiform operation throughout the train. f The emergency application valve device |l3 comprises a piston 68 having at one side a chamberl 69 containing e spring 10 acting on said piston. I@ Secured to the opposite side of said piston is a hollow sleeve 1i telescopically containing a valve piston 12, which is normally pressed into engagement with a seat rib 13 by a spring 14. The sleeve 1| is provided with a plurality of stop 15 pins 15 adapted to slide in corresponding slots 18 in the valve piston 12 for limiting the relative outward movement of valve piston 1.2 to sleeve l.

4 The vent valve device vI4 comprises a vent vaive 11 contained ein a chamber 18 and .a piston 90 connected to said vent valve-by a stem 19 for 5 operating said vent valve which is normally pressed into engagement with a seat rib by a spring 8|. The piston 90 has 'at one side/a chamber 82, and the other sl-:le of said piston is open through a plurality of passages 9| to the 10 vent valve chamber 18.

The-cut-out valve deviceE comprises a body containing a plug valve 83 movable from one to the other oi.' the two positions shown in Figs. 1 and 7 by a handle 84. The plug valve is provided' 15 with three ports, a port 85 for establishing communication from the brake pipe 4 to the brake controlling valve device I, a port 86 for establish-fy ing communication from the iiuidpressure supply pipe 5 to the supply reservoir 2 by way oi the 2U check valve device 1, and a port 81 arranged at right angles to ports 85 and 86 and adapted in the cut-out position shown in Fig. 7, to connect the brake cylinder pipe v88 to an atmospheric passage 89. 25

The brake pipe 4 and fluid pressure supply pipe 5 are connected between the cars of a train by means of the usual flexible hose 92 and hose couplings 93. The brake pipe` 4 is supplied with huid under pressure by the operation of a brake valve 30 device (not shown) in the usual well known manner, and the iiuid pressure supply pipe 5 is connected directly to a source of fluid under pressure such'as a main reservoir (not shown? o r a fluid compressor (not shown). 35

In operation, fluid under pressurev from the fluid pressure supply pipe 5 ilows through the check valve device 1 to the iiuid pressure supply reservoir 2, thereby charging vsaid reservoir. From the supply reservoir 2 fluid underk pressure 40 flows through pipe 94 to the brake controlling valve device l and from thence vthrough passage 95 to the release valve chamber 49. From cham.- ber 49 uid underlpressure ows through a passage 96 to the service application control valve 45 chamber 38 and from thence through passage 91, a choke plug 98 and passage 99 to chamber 26 at the lower side ci the graduated release valve piston 25 and also fr-em passage 99 to the poppet valve chamber 55 of the release ensuring valve 50 Fluid under pressure also ilows from the supply reservoir passage-95 through passage` |00, choke plug |0| and passage |02 to diaphragm chamber 62 of the reiease ensuring `valve device |2, and 55 from the release vvalve chamberv 49 through a port |03 in slide valve 50, passage |04 and a choke plug |05 to the equalizing valve chamber I9.

-At the same time as iluid under pressure is thus being supplied to the brake controlling valve de- 60 vice I from the supply reservoir 2, fluid under pressure also ows from the brake pipe 4 throughv passage |1 in the brake controlling valve device to the vent valve chamber 18 and to the equalizing piston chamber I6 and from said 4chamber 65 through passage |06 to diaphragm chamber 60 of the release ensuring valve device I2.

With the equalizing piston I5 in the release position, as shown in Fig. 2 of the drawings, fluid n under pressure ilows from chamber' I6 through 70 passage |01, past a ball che-ck valve |08 to passage |04 through which iiuid' under pressure is also being supplied from the supply reservoir 2.

Fluid under pressure thus being supplied from the supply reservoir 2 and brake pipe 4 to passage 75 I 04 and from thence through choke plug |05 to the equalizing valve chamber I9, flows from said chamber through passage 20 to the control chamber V2|,`thereby charging said chambers to brake pipe pressure and supply reservoir pressure; which normally are equal.

Fluid under pressure also ows from the equalizing piston chamber I6 through a feed groove |09 around the piston I5 to valve chamber I9. This ilow through the feed groove |09 is not essential to the operation of the brake controlling valve device but is provided to ensure equalization of pressures on the equalizing piston I5 when said piston is in release position, as shown in Fig. 2 of the drawings.

With the equalizing valve device in the release position, uid under pressure ows from the valve chamber I9 through passage I|0 to therelease valve piston chamber 41. The fluid pressures thus equalize on the opposite sides of the piston 46 and said piston and the slide valve 50 are maintained in therelease position shown in the/drawings by the pressure of spring 48. In the release position of slide valve 50, the brake cylinder 3 is open to the atmosphere through pipe 88, passage choke plug ||2, passage H3, cavity ||4 in said slide valve and an atmospheric passage II5.

Chamber 39 at the upper side of diaphragm 42 of the service application control valve device |0 is at all times open to the atmosphere through the atmospheric passage ||5, and in the release position of the equalizing slide valve 22, iiuid under pressure is supplied through passage ||6 to chamber 43 at the lower side of said diaphragm. The pressure of i'luid in chamber 43 holds valve 31 seated and valve 36 unseated against the opposing pressure of spring 45. With valve 36` unseated, fluid at supply reservoir pressure flows from chamber 38 to chamber 40 and from thence through passage 4| to the spring side of the valve piston 32. The valve piston 32 is thus held seated f against the seat rib 35 by the pressure of uid in chamber 33 and the pressure of spring 34 against I the opposing pressure of uid supplied from chamber 38 through passage ||1 to cavity ||8 outside of said seat rib.

With the equalizing valve chamber I9 charged to brake pipe pressure and chamber 26 at the opposite side of the graduated release piston 25 charged with iiuid from the supply reservoir, which pressure equals brake pipe pressure, said piston is maintained in its lower position by'the pressure of spring 28. The diaphragm 6| of the release ensuring valve device is also subject to the opposing pressures of the brake pipe and supply reservoir and when the equipment is completely charged and said pressures are equal, the spring holds the valve 59 unseated. Brake pipe pressure is thereby permitted to flow past the valve 59 to chamber'63 and from thence through passage I9 to piston chamber 52 and from thence through the feed groove |20 to chamber 53. Passage |2I leading from the piston chamber 53 is normally lapped by the equalizing slide valve 22, so that the pressures equalize on the opposite sides of the piston 5| and the spring 51 holds the poppet valve 54 seated.

Fluid under pressure supplied from the brake pipe to the vent valve chamber 18 ows through port |2| in the vent valve piston 90 to chamber 82 and from thence through passage |22 to the emergency application valve piston chamber 69. Passage |22 is connected by way of passage |23 to the seat of the equalizing slide valve 22 and is normally lapped by said slide valve, so that the pressures in chambers 82 and 69 equalize with brake pipe pressure. This permits spring 8| to hold the vent valve 11 seated against the seat rib 80, and spring 10 to hold the piston 68 seated against the seat rib |24. With the piston 68 in this position, the vvalve piston 12A is pressed into engagement withv seat rib 13 by the pressure of spring 14.

When the equalizingl slide valves 22 and 23 are in the full release position shown in Fig. 2, a quick service chamber |25 is connected with the atmosphere through passage |26, port |21 in the main slide valve 22, cavity 28 in the auxiliary slide valve 23, port |29 and cavity |30 in the main slide valve 22 and an atmospheric passage |3I.

In order to effect a service application of the brakes, the pressure of fluid in the brake pipe 4 is gradually reduced in the usual manner and a corresponding reduction occurs in the connected equalizing piston chamber I6.

When the brake pipe pressure in piston chamber I6 becomes thus reduced a predetermined degree below the control chamber pressure in chamber I9, the equalizing piston I5 is operated to move the auxiliary slide valve 23 upwardly from release position to quick service position, in which position the piston stem 24 engages the lower end of the main slide valve 22 and communication through the feed groove |03 is closed.

The movement of the equalizing piston I5 and auxiliary slide valve 23 temporarily ceases in quick service position for the reason that insuflicient pressure differential is at this time acting on said piston for moving the main slide valve which is provided with a cavity |30 for subjecting a predetermined area of its seating face to atmospheric pressure so as to increase its resistance to movement to a predetermined degree for reasons which will be hereinafter more fully A explained.

In quick service position of the auxiliary slide valve 23, a cavity |32 connects ports |33 and |21 in the main slide valve 22. Port I 3-1 registers With passage |34 which is connect-ed through passage |06 to the brake pipe passage I1, so that iiuid under pressure is permitted to flow from the brake pipe 4 through passages |06 and |34, port |33, cavity |32 in the auxiliary slide valve 23 and port |21 to passage |26 leading to the quick service chamber |25, thereby effecting a. local quick service reduction in brake pipe pressure for rapidly transmitting the brake pipe reduction serially from car to car through the train.

When a predetermined reduction in brake pipe pressure, of for instance four pounds, is obtained by the combined operation of the usual brake valve device (not shown) and the quick service action, the pressure of fluid in chamber I9 shifts the equalizing piston |5 and slide valves 22 and 23- to service position, shown in Fig. 3 of the drawings, in which position the piston I5 engages the movable stop 30.

In service position, passage |26 is lapped so that the quick service volume |25 is isolated, but further quick service action is eiected by venting iiuid under pressure directly from the brake pipe to the atmosphere through passages I1 and |34, port |31 in the main slide valve 22, port |38 and cavity |28 in the auxiliary slide valve 23, port |29 and cavity |30 in the main slide valve 22 and atmospheric passage |3I. This further quick service venting from the brake pipe hastens the rate of brake pipe reduction and it further has the eiect of smothering the turbulence created in the brake pipe by the initial quick service venting" to the quick service volume |25, so as to obtain a more, uniform brake pipe reduction. This nal quick service venting of uid under pressure from the brake pipe to the atmosphere is also desirable from another standpoint in that it ensures local quick service venting of uid under pressure from the brake pipe, if for any reason the piston I5 and slide valves 22 and 23 fail to stop in quick service position, but instead move directly to service position upon a reduction in brake pipe pressure. Al further reason forv this iinal quick service venting of iiuid under pressure directly from the brake pipe to the atmosphere is that it operates to efl'ecta quick service action upon successive reductions `in brake pipe pressure in graduating an appli- 'covered by the auxiliary slide valve 23 and registers with passage |36 leading yto the atmospheric passage I3I. This permits iiuid under pressure to flow from chamber I9 and the connected control chamber 2|, through passage 20 to the atmosphere at'substantially the same rate as the brake pipe pressure is being reduced.

In service position of the equalizing valve device, iluid under pressure is vented from the release piston chamber 41 to the atmosphere through passage IIII, port |35 in the main slide valve 22, cavity |28 in the auxiliary slide valve 23, port |29 and cavity |30 in the main slide valve 22 and atmospheric passage I3I. This permits the supply reservoir pressure in the release valve chamber 49 to shift the piston 46 and slide valve 50 upwardly against the pressure of spring 48 and until the piston engages a gasket |39.

In this position passage |04 is lapped so as to prevent further rlow of fluid from chamber 49 to the equalizing valve chamber I9, and passage II3, which is connected by a passage III to the brake cylinder pipe 88, is also lapped.

Fluid under pressure is also vented from diaphragm chamber 43 vof the service application control valve device through passage' IIB, port 200 in the main slide valve 22, cavity |28 in the auxiliary slide valve 23, passage |29 and cavity |30 in the main slide valve 22 and atmospheric passage I 3 I. This permits the pressure of spring 45 to seat valve 36 so as to cut off the supply of uid under pressure to the service application valve chamber 33. 'I'he seating of valve 36 unseats valve 31 which vents iiuid under pressure from the service application valve chamber 33 through passage 4|, chamber 40, chamber 33 and atmospheric passage ||5.

With the service application valve chamber 33 thus connected to the atmosphere, supply reservoir pressureacting in cavity I I8 on the opposite side of the valve piston 32, moves said valve piston away from the seat rib 35 against the pressure of the spring 34. This permits iluid under pressure to iiow from the supply reservoir 2 to the brake cylinder 3 by way of pipe 94, passage 95, valve chambers 49 and 38, passage II1, past the valve piston 32 to chamber |40 and from thence through passage I 4|, port |42 in an application control plug valve |43, passage III and brake cylinder pipe 88, lthe rate of flow being governed bythe restriction or choke I 44 in port I 42. Fluid under pressure thus supplied to the aosaiss I brakecylinder 3 effects an application o! the brakes in the usual manner.

. Fluid under pressure continues to-be supplied to the brake cylinder up to equalization with the pressure of iiuid supplied to the supply reservoir 2, if the equalizing valve device 3 is maintained in the service position bya continued reduction in brake pipe pressure.

lf, however, itis desired to limit the degree usual brake valve device (not shown) is operated so as to prevent any further reduction in brake pipe pressure by way oi the brake gvalve A device. The brake pipe reduction continues,

however, through passage |34 containing a choke plug 202, port |31 in the main slide valve 22, port'I38 and cavity .|20 in the auxiliary slide valve 23, port |29 and cavity |30 in the main slide valve 22 and atmospheric passage- 3| but, due to the restricted flow through said choke plug the rate of reduction in brake pipe pressure is slower` than the pressure in valve chambe'r I9 and the connected control ,chamber 2l reduces through port |35 in the main slide valve, passage |36 and atmospheric passage I3I. As a result, the pressure in valve chamber I9 becomes lower than the brake pipe pressure in chamber I6, and the differential moves the piston I5 and auxiliary valve 23 downwardly to service lap position in which the piston stem 24 engages the main slide valve 22. Further movement is prevented by the resistance of the main slide valve 22. g

In service lap position, the release valve piston chamber 41 is maintained open to the atmosphere through passage IIO, cavity I30Lin ythe main equalizing slide valve 22 and atmospheric passage I3I, so that piston 46 and slide valve 50 are maintained ,in their upper position as in eiecting a service application of the brakes. The brake cylinder passage II3 is thus maintained lapped.

When the equalizing piston I5 and auxiliary slide valve 23 move to service lap position, port 200 through the main slide valve 22 is uncovered by the auxiliary slide valve 23 and this permits iluid under pressure to flow from the equalizing valve chamber I9 through port 200 and passage II6 to diaphragm chamber 43 of the service application `control valve device I0. The pressure of fluid thus supplied to chamber 43 deflects the diaphragm 42 upwardly, seating valve 31 and unseating valve 36. The seating of kvalve 31 closes communication from chamber 43 of the service application valve 9 to the atmosphere and the unseating of valve 35 permits iiuid under pressure to iiow from chamber 38 to chamber 40 and from thence through passage 4I to chamber 33, thereby equalizing the fluid pressures acting on the opposite sides of the service application Valve piston 32, which permits spring 34 to shift valve piston 32 into engagement with seat rib 35. 'Ihis-cuts off the flow of iluid under pressure from cavity I|8 to chamber |40 and from thence to the brake cylinder 3 through passage |4I, passage |42 in the plugsvalve |43, passage I|I and pipe 88, thereby limiting the pressure in the brake cylinder to a predetermined degree proportional to the degree of brake vpipe reduction.l

When the equalizing valve device moves' to service lap position, further quick service `venting of fluidr from the kbrake pipe through passage |34, port |31 in the main slide valve, port Iss and cavity Iza in the auxiliary slide valve 23, port |29 and cavity |30 in the main slide valve 22 and atmospheric passage I 3| is cut oi! due to the movement of the auxiliary slide valve 23 lapping the port |31.

If a further service application of the brakes is desired, a further reduction in brake pipe pressure is eiiected by the brake valve device in the usual manner and this causes the equalizing piston I and auxiliary slide valve 23 to move from service lap position to service position, in which the mechanism again operates in the same manner as herelnbefore described to supply more fluid to brake cylinder 3 and thus effect a further application of the brakes.

In the manner just described, the brake cylinder pressure may be increased in steps in accordance with the degree of brake pipe reduction effected, and thus a graduated application of the brakes is obtained.

When the equalizing valve slide valve 23 is moved from service lap to servicepositionl to eiect a further application of the brakes, communication is again established from the brake pipe passage |34 to the atmospheric passage I 3I so as to effect a local quick service reduction in brake pipe pressure to hasten the increase of brake application and ensure movement of the equalizing valve device to service position. Ihis quick service action is eiective upon every successive brake pipe reduction in graduating an application of the brakes.

Diaphragm chamber 60 of the release ensuring valve device |12 being open through passages I06 and -I1 to the fbrake pipe 4, the pressure in said chamber reduces as brake pipe pressure is reduced. When a slight reduction in pressure, of for instance less than one pound, is made in diaphragm chamber 60, supply reservoir pressure acting in chamber 62 on the opposite side of diaphragm GI deflects said diaphragm downwardly and seats valve 59 against the opposing pressure of spring 65. Now, when the equalizing valve device moves to service posi- V. tion, passage I2| is connected to the atmosphere through cavity |30 in the main slide valve 22 and the atmospheric passage |3I. Passage I2I connects to pistonchamber 53 in the release ensuring valve device I2. Chamber 53 is open through feed groove |20 to chamber 52 which is also connected through passage |I9 to chamber 63. Fluid under pressure is thus vented from the chambers 63, 52 and 53 to the atmosphere through passage I2I, the feed groove |20 being of sufficient size to permit fluid under pressure to ilow from chambers 63 and 52 to chamber 53 at such a rate as to prevent obtaining sufficient diierential on the piston 5| to unseat the poppet valve 54.

The chamber 53 is thus vented to the atmosphere in effecting an application of the brakes,

so that when the brake pipe pressure is in-` creased to effect a release of the brakes, uid under pressure supplied to chamber 52 will opcrate pieton 5| to unseat valve 54 for venting fluid under pressure from the .equalizing valve f chamber I9 and chamber 26 at the lower side of the graduated release stop device 21 so as to ensure movement of the equalizing valve device to full release position, shown in Fig. 1, as will be hereinafter fully described.

Also, in effecting an application of the brakes, when the control chamber pressure in the equalizing valve chamber I9 is reduced a predetermined degree below the control reservoir pressure acting in chamber 2.0 on the opposite side of the graduated release valve piston 25, said piston is moved `upwardly against the pressure of spring 28. This upward movement is limited by the engagement of said piston with gasket |45, and is adapted to thrust the stop 21 into valve chamber I9, as shown in Fig. 3, for limiting the release movement of the equalizing piston I5 and slide valves 22 and 23 in releasing after an application oi.' the brakes as will now be described.

When it is desired to effect .a release of the brakes after an application, iluid under pressure is supplied to theY brake pipe 4 by the operation of the brake valve device (not shown) in the usual manner, and ows from the brake pipe through passage I1 to the equalizing pist-on chamber I5. When the pressure in chamber I6 is thus increased a predetermined degree above the reduced control chamber pressure in valve chamber I9, the piston I5 is moved downwardly, carrying with it the auxiliary slide valve 23 and the main-slide valve 22. This downward movement ceases in graduated release position, shown in Fig. 5, in which position the piston stem 24 engages the graduated release piston stop 21 which is thrust into the chamber I9 by the pressure d iierential acting on piston 25 as hereinbefore described.

In the graduated release position, iiuid under pressure is supplied from the equalizing valve chamber I9 through passage IIS to diaphragm chamber 43 of the service application control valve device I0. The pressure of iuid in said chamber deilects the diaphragm 42 upwardly for seating valve 31 and unseating valve 36. With valve 3| unseated, fluid under pressure is supplied from valve chamber 38 to chamber 40 and from thence through passage 4| to chamber 33 at the spring side of the service application valve piston 32, which permits the iiuid pressure differential acting on said valve piston and the pressure of spring 34 to hold said valve piston in engagement with the seat rib 35 so as to prevent iluid at supply reservoir pressure from flowing from cavity ||8 to passage I4I and fromv thence to the brake cylinder 3.

Fluid under pressure is supplied from valve chamber I9 through port 200 in the main slide valve 22 and passage I|0 to piston chamber 41 of the release valve device II, when the equalizing valve device is in the graduated release position. The pressure of iiuid thus supplied to piston chamber 41 shifts the piston 46 and slide valve 50 Yto the release position shown in Fig. 2 of the drawings, in which position, iluid under pressure is vented `from the brake cylinder 3 through pipe 88, passage III, release choke plug II2, passage I I3, cavity I|4 inthe release slide valve 50 and atmospheric passage |I5, thereby effecting a release of the brakes.

At the same time as uid under pressure is being vented from the brake cylinder to the atmosphere, fluid under pressure is being supplied from the supply reservoir 2 to the equalizing valve chamber I9 and control chamber 2|, which is connected through passage 20 to chamber 9, by way of pipe 94, passage 95, release valve chamber 49, port |63 in the slide valve 50, passage I 04 and choke plug |05, thereby charging said chambers.

The iiow area of the choke plug |95 is such as to permit the equalizing valve chamber I9 and connected control chamber 2| to charge at a slower rate than the brake pipe pressure acting in the 4e'qualizing piston chamber |6 is increased, so that if the increag in brake pipe pressure is continuous, the equajiizing valve piston l5 and slide valves 22Wand 23 will remainin release position and the venting of fluid under pressure from the brake cylinder will be continuous.

It is the usual practice at present, however, to graduate the release of brakes,.or in other words to release fluid under pressure from the brake cylinder 3 in steps. In order to thus graduate the release ofi brakes, the brake pipe pressure is only; increased a certain amount. Now, when the pressure in the equalizing valve chamber and centrol chamber 2| is increased in the manner hereinbefere described, to a degree slightly l exceeding the Yincreased brakepipe pressure pistonfchamber |6, theequalizing piston Il5 and auxiliary slide valve 23 are shifted upwardly to release lap position in which the outer nd of the piston stem 24 engages the end of the V'inain slide valve 22 which prevents further movement. ln this position of the auxiliary slide valie 23, fluid under pressure is vented fromthe release piston chamber 51 through passage |250, port 200 in the main slide valve 22, cavity |253 in the: auxiliary slide valve 23, port |29 and cavity |30 in the main slide valve 22 and atmospheric passage |3I.

Y The pressure of vfluid in the release valve cham- `ton engages the gasket |39.

ber 49Y then shifts the piston ii6 and slide valve I n chamber I9 and control chamber 2|.

The iluid remaining in the brake cylinder is thus bottled up until a further increase in brake .pipe pressure VVis elected to again move the equalizing Yrpiston t5 and auxiliary slide valve 23A to the release position, shown in Fig. 5, and the apparatus will then operate as above described to effect another reduction in brake cylinder pressure, the degree of which reduction will be in preportionto the degree of increase of brake pipe pressure; e l

In the above manner the brake cylinder pressure may be Y'graduated oi in steps desired. It is evident that in thus graduating zhe release of brakes, the pressure in valve chamber I9 may be increased to substantiallythat carried in the brake pipe and acting in the equalia'ing piston chamber Il.` As hereinbefore described, it requires substantially a four pound pressure difierential on the equalizing pisten |5 to move said piston and the slider-valve 22 and 2L!Y to service application position on account of the predetermined loading of the slide valve 22 by the cavity |39. Said cavity is at all times open to the at-r mosphere and as a result, substantially the same differential is required on said piston to move the slide valves 22 and 23 from the graduated release position shown in Fig. 5 to the full release position shown in Fig. 2. Itis obvious that in graduating thel release of brakes if the pressure in valve chamber i9 is increased to within less than four pounds of the normal brake pipe pressure :carrieddt will not be possible to obtain-the required differential to move the equalizing valve deviee from the graduated release position sh-'l-wn in Eig. 5 to the full release position shown in It is possible, with my invention to permit a graduated release of fluid from the brake cyiin- .anotar-1sA v Y Vder tothe ipoint at which the pressure in the Aequalizing valve chamber becomes substantially equal to thenormalgbrake pipe pressure, for the,

reason that-' I have provided means, operative when the brake pipe pressure is increased to a devalve device'Y |2 to operate, when the brake pipe becomes substantially charged to the normal pressure, to reduce the pressure in the equalizing valve chamber I9 a suiicient degree'below the brake pipe Ypressure'in chamber |6as to obtain therequired pressure differential on piston I5 to move the slide valves 22 arid 23 to their full remosphere through passage i2l, cavity |30 in the main slide valve 22and atmospheric passage |3| when the main slizle valve22A is vin graduated release position shown in Fig. 5. Chamber 52 at theopposite side of piston 5| being connected to chamber 53 through the groove |20, both sides of said piston aresubject Yto atmospheric pressure and spring 52 holds the poppet-valve 5t` seated against the seat rib 58.

The pressure of iluid in the supply reservoir 2 and in the connected diaphragm chamber 62 of the release ensuring valve device is maintained byithe supply through supply pipe-5, and m releasing the brakes is therefore'substantiallconstant. The pressure in chamber 60 at the epposite side of the diaphragm f 6| increases'with brake pipe pressure. The spring 651s so adisted that when the brake pipe pressure'has been increased to Within possibly less than one pound of the supply reservoir pressure in diaphragm chamber 62, said spring unseats the valve 59.

With valve 59 unseated, fluid ait brake pipe pressure ilows from diaphragm chamber 60 to chamber 63 and from thence through passage H9 to piston chamber 52. f- The rate of this supply to chamber 52 exceeds the venting capacity of groove |20 around the piston 5|. Consequently, a pressure builds up in piston chamber 52 and moves said pistondownw'a'rdly against the opposing pressure ofY spring iil. 'Ihis unseats the poppet valve 54 and connects chamber 55 past the fluted valve stem 56 to chamber 53 which is open to the atmosphere throughi'passage |2|, cavity |30 in the mainslide valve 22 and atmospheric ,passage |35.

Chamber 26 at the lower side of the graduated release valve .piston 25 communicates through passage SQ* with poppet valve chamber 55 which is open to the atmosphere, so that fluid under pressure is vented from chamber 26. Chamber 26 is also open to the supply reservoir 2 through passage 99, choke plug 98, passage 91,?2 valve chambers 38 and 4 9, passage 95 and pipe e4, but

the rate of supply to chamber 26./ from the sup-` piy reservoir 2 is so restricted by the choke plug 92, that the venting offluid under pressure from chamber 26 reduces the pressure in said chamber sufficiently that` the pressure of fluid Win the equalizing valve chamber |9 in addition to the pressure of spring 28 shifts the graduated release valve piston 25 and stop 21 to their normal position as shown in Fig. 2.

When the poppet valve54 isopen, :duid under pressure is also vented from the equalizing valve chamber I9 and control chamber 2| through passage 20, past the ball check valve |46, through passage |41 and chamber 55 which is open ythrough chamber 53 togpassage I2|. This permits the pressure of fluid in valve chamber I9 to reduce at a rate exceeding the rate of supply from the supply reservoir 2 through the choke |95.

When the Apressure in valve chamber I9 is thus reduced a predetermined amount below the brake pipe pressure in chamber I6, the piston I5 and slide valves 22 and 23 are moved to their full release position shown in Fig. 2.

It will be noted that, since the release ensuring valve device I2 is subject to the constant pressure in chamber v(i2 and the xed pressure of spring' 65, it will at all times operate, as above described, when the brake pipe pressure is increased to a predetermined degree, therefore, the movement of the equalizing piston I5 and slide valves 22 and 23 to thefull release position, is positively ensured under all conditions. For example, if there should be sufficient leakage from the brake pipe past the piston I5 to valve chamber I9, when the brake pipe pressure is increased, to prevent the creation of a suiiicient differential of pressures to move the piston I5 and slide valves 22 and 23 inwardly from application position to release position, then as soon as the brake pipe pressure has been increased substantially to the normal pressure carried in the brake system, the release ensuring valve device will operate to effeet a venting of iluid from the valve chamber I9, until a suicient diierential of pressures is created on the piston I5 to ensure its movement to release position and the consequent release of the brakes.

In releasing the brakes, fluid under pressure flows from the supply reservoir 2 to the equalizing valve chamber I9 and control chamber 2| for charging said chambers. This iiow tends to temporarily reduce the pressure in said reservoir and in the connected release ensuring valve diaphragm chamber 62, and cause premature operation of the release ensuring valve device. To avoid this undesirable action, choke IIlI is provided and tends to maintain the pressure in diaphragm chamber 62 substantially constant even though the supply reservoir pressure may vary slightly.

In full release position of the main slide valve 22, passage I2I is lapped, which prevents further venting of fluid under pressure from the valve chamber I9 past the ball check valve |46 and the unseated poppet valve 54. The pressure then builds up in the equalizing valve chamber I9 and control chamber 2| by flow of uid under pressure from the supply reservoir through choke |05, and finally the pressures equalize on the opposite sides of the equalizing piston I5 through the feed groove |09.

After passage 2| is lapped by the main slide valve 22, the pressure builds up in the graduated release piston chamber 26, by ow of iiuid under pressure from the supply reservoir 2, through the croke 98, equal to the pressure in the equalizing valve chamber I9 which permits spring 28 to hold the piston 25 and stop 21 to the normal release position shown in Fig. 2. Fluid at the pressure supplied to chamber 26 also ows from passage 99.110 poppet valve chamber 55 and from thence past said valve and the uted valve stem 56 to piston chamber 53. Fluid at brake pipe pressure is acting in chamber 52 at the opposite side of piston 5|, but upon substantial equalization of the pressures on the opposite sides ot said piston," spring 51 shiits'the poppet valve 54 into engage-,-

mentf with seat rib 58 so as toclose communica-y tion from chamber Il to chamber 53. This is valves22 and 23, uid under pressure is vented from the quick service chamber |25 through passage I28, port |21 in the main slide valve 22, cavity |29 in the auxiliary slide valve 28, port |29 and cavity |30 in the main slide valve 22 and the atmospheric passage I8I.

As nereiiibefore mentioned, the cavity nu in the main slide valve 22 is provided for at all times exposing a predetermined area of the seating tace of said slide valve to atmospheric "pressure through the atmospheric passage |3I. This causes said slide valve to be pressed into engagement with its seat with a predetermined force,

yand consequently a predetermined diiierential on the equalizing piston I5 of for instance four pounds, is required to move said slide valve. 'I'he piston I5 and auxiliary slide valve 23 are however intended to be sensitive to brake pipe pressure variations and to move to quick service position upon a light reduction in brake pipe pressure oi for instance one pound. The degree o1' brake pipe reduction eilected by equalization of the brake pipe and quick service chamber |25 is intended to be about two pounds, so that if a one pound reduction in brake pipe pressure is unintentionally obtained and the equalizing valve device moves to quick service position and a further two pound reduction in brake pipe pressure is obtained, the brake pipe pressure will not be sufficiently r'educed to cause movement of the equallzing valve device to service position. Consequntiy, the equalizing valve device is sensitive to a light brake pipe reduction to effect the desired quick service action but is stable against unintentional movement to service application position.

If it is desired to eii'ect an emergency application of the brakes, a sudden reduction in brake pipe pressure is eiected in the usual manner. A corresponding reduction occurs in the equalizing piston chamber I6 and the pressure of fluid in the equalizing valve chamber I9 then shifts the equalizing piston I5 and slide valves 22 and 23 upwardly to emergency position in which said piston engages a gasket |48, as shown in Fig. 4.

In emergency position oi' the main equalizing slide valve 22, iiuid under pressure is vented from the vent valve piston chamber 82 and emergencyl piston chamber 69 to the atmosphere through passages |22 and |23, cavity |49, passage |50 and cavity |30 in the main slide valve 22 and atmospheric passage I3I.

'I'he venting of uid under pressure from the vent valve piston chamber 82 permits brake pipe pressure acting in chamber 18 at the opposite side of said piston to move said piston outwardly, thereby pulling the vent valve 11 away from the seat rib 80 against the opposing pressure of the spring 8|. With the vent valve unseated, uid under pressure is locally vented directly from the brake pipe 4 to the atmosphere through passage |1, past the vent valve 11 and through the atmospheric passage |5I, so as to serially propagate quick action in the usual manner. when' rib 80.

With the equalizing slidevalve 22 in emergency position, fluid under pressureis vented from piston chamber 41 of the release valve device to the atmosphere through passage IIO, cavity |30 in said slide valve and the atmospheric passage I3I. 'Ihe piston 48 is then'shiited upwardly by the pressure oi'y iluid in valve chamber 49and moves slide valve 50 so as to lap passage |04 and the'brake cylinder passage I I3 in the same manner as in eiecting a service application ci.' the brakes. Likewisedluid under pressure is vented from diaphragm chamber 43 of the service application control valve device I to the atmosphere through passage I I6, cavity |30 in the slide valve 22 and atmospheric passage I3I. vThis permits spring 45 to seat valve 36 and unseat valve 31 so as to vent fluid under pressure from the application valve piston chamber 33 to the atmosphere through passage 4I, chamber 40, valve chamber 39, and the atmospheric passage |I5. With the application valve piston chamber 33 thus vented, supply reservoir pressure acting in.

cavity I|8 at the opposite side ofthe valve piston 32 moves said valve piston away from seat rib 35, thereby permittingfiuid from the supply reservoir 2 to ow through cavity IIB to chamber |40 and from thence through passage I 4| restriction |44 in plug valve |43, passage lli and pipe 88 to the brake cylinder 3 inthe same manner as in eiecting a service application of the brakes. y

Fluldrunder pressure supplied to passage I 4I ows to chamber` |54 and acts on the area. of the emergency valve piston 12 within the seat rib 13. With the emergency piston chamber 69 open to the atmosphere, the pressure of fluid in chamber |54 movesI the valve piston 12 away from the seat,

rib 13 and shifts the piston 68 into engagement with the gasket |52. In this position of the valve piston'12, iluid under pressure iiows from chamber |54 directly to passage II| andv from thence through pipe 88 to the brake cylinder 3. 'I'he supply of iluid through the emergency valve is independent of the plug valve |43 and permits uid under pressure to flow to the brake cylinder at a faster rate than is obtained in a service application of the brakes through the plug valve |43 by itself.

The service'application valve piston 32 remains in its lower position away from the seat rib 35 as long as the equalizing valve device remains in emergency position and maintains the valve piston chamber 33 vented through the operation of the service application control valve device I0. As a result, the pressures in the brake cylinder 3 andk supply .reservoir 2 equalize and since the supply reservoir 2 is charged through the supply pipe 5, which is connected to any suitable source of uid under pressure, the brake cylinder pressure will build up in an emergency application oi' the brakes to the pressure of uid in the supply pipe and will then be maintained against leakage in accordance with the rate of supply of fluid under pressure to the supply pipe 5.

One particular advantage of my improved brake equipment is that the high emergency brake cylinder pressure can be obtained at any time, for the reason that in emergency, the brake cylinder 2 is placed in direct communication with the source of supply of duid under pressure throughl the supply pipe.

In emergency position of the equalizing valve device, uid underv pressure is vented from valve chamber I9 and the connected control chamber 2| through port k|35 inthe main slide valve 22, passage |36 and atmospheric passage |3I. the pressure in said chamber Ais thus reduced to below the value of the spring 3| ,said spring shifts the piston I'and the auxiliary slide valve 23 to emergency lap position in which the piston stem engages the upper end'oi the main slide valve. Another important feature is that the pressure in the valvechamber I8 is reduced, as just described, to a low degree, as for instance nearly to atmospheric pressure if desired, for the reason Whenf that there is no fluid pressure acting to unseat the main slide valve 22 in emergency position and by reducing the pressure in the valve chamber to a. low degree, the movement of the equalizlng valve device to graduated release position shown in 5 is facilitated by a relatively low brake pipe pressure. in releasing the brakes after an emergency application, as will now be described.

To release the brakes after an emergency application, uid under pressure is supplied to the brake pipe 4 and to the piston chamber` I5 of the equalizing valve device 8. When the brake pipe pressure acting on the upper iace of the equalizing piston I5 is thus increased a predetermined degree over the reduced pressure in the equalizing valve chamber I9, the piston l5 an'd slide valves 22 and 23 are shifted to graduated release position, as shown in Fig.- 5, in which position, the piston stem 24 engages the graduated release piston stop 212 In graduated release position of the main slid valve 22,/uid under pressure is supplied through passage I6 to diaphragm `cluan'iber 43 of the service application control `valve device |0` and deilects the diaphragm 42 upwardly, seating valve 31 and unseating valve 36 which permits fluid under pressure from the supply reservoir v2 to ilow from chamber 3 8 to chamber 40 and from thence through passage 4| to the spring side of the service application valve piston 32. l The pressure of iiuid thus suppliedto chamber 33, plus the pressure of spring 34 seats the service application valve piston against seat rib 35 so as to prevent further flow of fluid under pressure to the brake cylinder 3.

At the same time as the supply of iiuid to the brake cylinder 3 is cut oil', fluid under pressure is supplied from the equalizing valve chamber I9 through port 200 in the main slide valve 22 and passage I.I0 to the release valve piston chamber 41. The pressure of fluid thus supplied to chamber 41 plus the pressure of spring 48 shifts the piston 46 and slide valve 50 to release position, in which fluid under pressure is`vented from the brake cylinder 3 through 4pipe 88, passage |II, choke ||2, passage I|3, cavity II4 and atmospheric passage I I5. At the Sametime, supply reservoirpressure is supplied from valve chamber 49 through port |03 in slide valve'50, passage |04 and choke plug |05 to the equalizing valve cham- 'ber I9 and control reservoir 2|, thereby charging release position, in which a complete release of the brakes takes place.

With the equalizing slide valve 22 in the graduated release position and full release position, passage |23 is lapped. Passage |23 connects through passage |22 to the vent valve piston chamber 82 and the emergency valve piston chamber 69. As the brake pipe pressure is increased, fluid from the brake pipe flows through passage |1 to vent valve chamber 18 and from thence through ports 94, port |2| in the vent valve piston 30 to chamber 82. and from chamber 82 through passage |22 to the emergency piston chamber 69. The increase in pressure in chamber $9 acting on the emergency piston 68 shifts said piston and the valve piston 12 to the left until said valve piston engages the seat rib 13 so as to close communication from chamber |54 to the brake cylinder passage After the valve piston 12 thus engages seat rib 13, further relative movement of the piston 68 occurs until said piston engages the seat rib |24.

With the emergency valve piston 12 thus engaging the seat rib 13, the emergency by-pass around the plug valve |43 is closed.

The application control plug valve |43 is adapted to be turned by a handle |55 to a plurality of different positions, such as from the position shown in Fig. 2 of the drawings to the position shown in Fig. 6 oi' the drawings, and said plug valve is provided with a plurality of through ports containing restrictions of diierent sizes. In Fig. 2, iiuid under pressure is supplied to the brake cylinder through the port |42 containing the restriction |44, but if the plug valve is turned to the position shown in Fig. 6, fluid under pressure is supplied to the brake cylinder through port |55 containing a restriction |51 which is different in size from the restriction |44 in port |42. This is desirable in that the plug valve may be turned to a position corresponding to the load carried by a car, so that when the car is loaded the brake cylinder pressure may build up faster than when the car is not loaded. By thus permitting a more rapid build up of brake cylinder pressure on the loaded car, the braking power developed on said car may increase nearly in synchronism with that on an empty car in which the rate of increase in brake cylinder pressure is at a slower rate as controlled by the plug valve |43 in a different position. By thus varying the rate of build up of pressure in the brake cylinder on empty and loaded cars in a train so as to obtain a nearly synchronous braking power on all cars, the decelerating of a train is obtained more smoothly and in a minimum of time.

Another desirable application of the plug valve |43 is that it may be adjusted to permit the same rate of build up in brake cylinders of various volumes. It is well known that the brake cylinder volume required for a car, either in a single brake cylinder or a multiplicity of brake cylinders, depends primarily upon the weight of a car. Thus for various weights of cars the brake cylinder volume will be different, but by the use of the plug valve |43, the rate of brake application on the cars in a train can readily be sustantially synchronized by turning the plug valve |43 to the proper position.

The adjustability of the rate of ow of uid to the brake cylinder in eiecting an application of the brakes is very important as pointed out above and my improved valve mechanism is especially adapted to this purpose for the reason that the equalizing valve device 8 is merely a pilot for the service application valve device I and release valve device ||A and the operation of the equalizing valve device in effecting an application of the brakes is controlled by the time required to eilect a reduction in pressure in the valve chamber I9 and control chamber 2|, which are of ilxed volume under all conditions. This time operation of the equalizing valve device is fixed, but the brake cylinder pressure obtained is not only governed by this xed time but in addition by the rate at which uid is permitted to ilow to the brake cylinder as governed by the controlling restriction in the plug valve |43. Hence, although the time which iluid may ilow to the brake cylinder is fixed, the brake cylinder pressure obtained in this xed time may be varied as desired.

The rate of release of the brakes after an application is not critical like the rate of application, but may be adjusted according to the brake cylinder volume by inserting the proper size of choke plug |I2.

If for any reason it is desired to render the brake controlling valve mechanism inoperative, the cut-out valve device 6 is turned from the cutin position shown in Fig. 2 of the drawings to the cut-out position shown in Fig. 7 of the drawings. In the cut-out position communication from the brake pipe 4 and supply pipe 5 to the brake controlling valve device and supply reservoir 2 respectively, is interrupted, and the brake cylinder pipe 88 is opened to the atmosphere through port 81 in the plug valve 83 and the atmospheric passage 89. 'Ihus if the brakes are applied at the time the brake controlling valve mechanism is cut out, they will be immediately released and not interfere with the train operation, or if the brake equipment is charged with iluid under pressure at the time it is cut out and due to the subsequent operation of the brake controlling valve device, on account of leakage, to supply fluid to the brake cylinder, the brakes will not apply due to the brake cylinder being opened to the atmosphere.

The check valve 1 is provided in the fluid pressure supply pipe to the supply reservoir 2 so that in case of leakage of luid under pressure from the supply pipe 2 or in case of a train break-intwo, the supply of uicl in reservoir 2 for applying the brakes will not be lost.

It will be noted that substantially all of the iluid under pressure employed for applying and releasing the brakes on the car comes from the fluid pressure supply pipe 5. A certain small amount may come from the brake pipe 4 for the purpose oi.' obtaining equalization oi.' pressures on the opposite sides of the equalizing valve piston I5 in releasing after an application of the brakes, but the primary purpose of the brake pipe is merely as a medium through which the brakes are controlled. As a result of thus providing a supply of uid under pressure on the car independent of the brake pipe, the brakes may be operated as rapidly as the brake pipe pressure may be varied.

While one illustrative embodiment of the invention has been described in detail, it is not my intention to limit its scope to that embodiment or otherwise than by the terms of the appended claims.

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a fluid pressure brake, the combination with a brake pipe and a quick service reservoir, of a valve device operated upon a reduction in pressure from said chamber for moving said pis-I 'with a brake pipe and a quick service reservoir,

of a valve device subject totheropposing pressures of the brake pipe and a chamber and Inovable upon a reduction in brake pipe pressure to quick service position for venting-duid under pressure from said brake pipe to said quick service reservoir, and movable upon a further reduction in brake pipe pressure to application position for venting duid under pressure from said brake pipe directly to the atmosphere and for venting fluid under pressure from said chamber for moving said valve device to lap' position, in which position, the ventinggof fluid-under pressure from said chamber and from' said brake pipe is cut oi. l Y

3. In a uid pressure brake, the combination with a brake pipe and a quick service reservoir, of a main slide valve, an auxiliary slide vvalve movable relative t said main slide valve, and a piston subject to the opposing pressures of the brake pipe and a chamber for moving said slide valves, said piston seing operated by a light reduction in brake pipe pressure toV move said auxiliary s'iide valve relative to said main slide valve for connecting said quick service reservoir to said brake pipe'and operated by a further reduction in brake pipe pressure to move said marin slider-valve for connecting said brake-pipe torthe atm-iosphere-and for venting fiuidunder ton and auxiliary slide valve inthe reverse dreetion relative to said main slide valve lor-cutting oil? the venting of uid under pressure from said chamber and from said brake pipe.

In a uid pressure brake, thei combination with a brake cylinder and a -brake pipe, orf an equalizing valve device movable upon a reduction in brake pipe pressure to service position for ef- 4fecting the supply of fluid under pressure to said brake cylinder and for venting duid under pressure from said brake pipe directly to the atmosphere, and'operative upon an increase in brake pipe pressure to eiect a release of fluid under pressure from said brake cylinder to the atmosphere and to close the atmospheric connection to said brake pipe. g; i

5. In a fluid pressure brake, the 'combination with a brake pipe and a brake cylinder, or valve means for controlling the supply and release of uid under pressure to and from said brake cylinder and for controlling the supply of fluid under pressure to Ya chamber, and an equalizing valve device operative by the pressure of fluid s in said chamber upon a reduction in brake pipe pressure te cause said valve means to operate to supply fluid under pressure Yto said brake cylinder and to cutoi the supply of uid under pressure td said chamber and operative upon an increase ini brake pipe pressure to cause said valve means tqoperate to vent iluid under pressure from said brake cylinder and to supply uid under'pressure to said chamber. Y

In a fluid pressure brake, the combination with a brake pipe and a brake cylinder, ofvalve means for controliing the supply and release of :duid under pressure to and fromsaid brake cylholding fiuid under pressure in said brake cylinaosai-is s inder and for rcontrolling the supply of fluid under pressure to a chamber, andan equalizing valve device operative by the pressure o! @uid/in said chamber upon a reduction in brake pipe pressure to vent iiuid `under pressure from said valve means for causing said valve means* to be cperated.,for supplying fluid under presssxre to said brake cylinder and for cutting oil the supply ci iiuid under pressure to said chaxnber, said equalizingVY valve device being operative upon an 10 increase in brake pipe pressure to supply iluid under pressure to said valve meai for operating said valve means to vent fluid under lpressure from said brake cylinder and to supply fluid under pressure to said chamber. I:

with a brake pipe, a. brake cylinder and a chamber, of valve means for connecting said brake cylinder with the atmosphere and for supplying uid under pressure to said chamber, and an equalizing valve device subject to the opposing pressures of the brake pipe and said chamber and operative upon a reduction in brake pipe pressure to vent luid under pressure from said chamber and to cause said valve means to operate to close thatmospheric connection to said 25 brake cyiinder and to cut oir the supply of fluid L under pressure to said chamber, said equalizing valve device being operative upon an increase in 5 brake pipe pressure to cause said valve means to l supply fluid under pressure to saidchamber and to connect said brake cylinder to the atmosphere. 8. In agiuid pressure brake, the combination with a brake pipe, a brake cylinder, and achamber, of valve means having a release position for l venting iiuid under pressure from `saldi brake 735, cylinder and for supplying fluid under pressure to said chamber, a lap position for holding the brake cylinder pressure and for cutting off thesupply of fluid under pressure to said chamber, and an Y equalizing valve device subject to `the opposing '40 pressures of the brake pipe and said chamber and operativeupon an increase in bra-re pipe pressure i to cause said valve means-to move-sto release position, said equalizing valve device Ybeing operative upon an increase inthe pressure in said chamber 45 over the brake pipe pressure to cause said valve means to move to lap' position. l

9. In av fluid pressure brake, the combination with a brake pipe, abra-ke cylinder, a source of iiuid under pressure and a chamber, of arelease valve device having a release position for venting fluid under pressure from said brake cylinder and for supplying duid under pressure from said source. to said ehambernand a lap position ioxLY holding duid under pressure in said brakecylinder and *for cutting off the supply of fluid under: pressure to said chamber, and an equalizing valvef device subject to the opposing pressures oi the brake pipe and said chamber and operative upon* 60 an increase in brake pipeY pressure over the pressure in said chamber to cause said release valve? device to move to release position, said edualizing Y valve device being operative upon an increase in pressure in said chamber over the pressure in said: 65

in ui vbrake pipe to cause said release valve device toV move to lap position. A*

10.`In'a iluid Vpressure brake, the combination with a brake pipe, a. brake cylinder, a source of fluid under pressure and a chan'iber,` of a release 70 valve device having a release position for venting fluid under pressure from brake cylinder der and for cutting oi the supply of uid under pressure to said chamber, an equalizing valve device subject to the opposing pressures of the brake pipe and said chamber and operative upon an increase in brake pipe pressure over the pressure in said chamber to cause said release valve de; vice to move to release position, said equalizing valve device being operative upon an increase in pressure in said chamber over the pressure in said brake pipe to cause said release valve device to move to lap position, and means for also supplying fluid under pressure from said brake pipe to said chamber when said equalizing valve device is operated by an increase in brake pipe pressure.

11. In a fluid pressure brake, the combination with a brake pipe and a brake cylinder, of a release valve device operated by fluid pressure upon a reduction in brake pipe pressure to close an atmospheric connection to said brake cylinder, resilient means, application valve means operated by said resilient means for controlling the supply of fluid under pressure to said brake cylinder upon a reduction in brake pipe pressure, said application valve means and release valve device being operated by iiuid under pressure to cut oii the supply of fluid under pressure to said brake cylinder and to vent fluid under pressure from said brake cylinder to the atmosphere upon an increase in brake pipe pressure, and an equalizing valve device operative in accordance with variations in brake pipe pressure to control the opera- `tion of said application valve means and said release valve device.

12. In a uid pressure brake, the combination with a brake pipe and a chamber, of a valve device operative in accordance with variations in iiuid pressure for controlling the release of the brakes and for controlling the supply of fluid under pressure to said chamber, a main valve for controlling the pressure on said valve device at one time,

'an auxiliary valve for controlling the pressure on said valve device at another time, a piston controlled by variations in the opposing pressures of the brake pipe and said chamber for operating said valves, and means operated upon a reduction in pressure in said chamberior defining the position in which the pressure of fluid on said valve device is controlled by said auxiliary valve.

13. In a uid pressure brake, the combination with a brake pipe and aisource of iiuid under pressure, of an equalizing valve device subject to variations in brake pipe pressure and having a full release position and a graduated release position for releasing the brakes, a stop device operated by the pressure of fluid in said source upon a reduction in brake pipe pressure for dening the graduated release position, and valve means operated upon an increase in brake pipe pressure for rendering said stop device ineffective.

14. In a iluid pressure brake, the combination with a brake pipe and a source of fluid under pressure, of an equalizing valve device subject to variations in brake pipe pressure and having a full release position and a graduated release position for releasing the brakes, a stop device operated by the pressure of fluid in said source upon a reduction in brake pipe pressure for defining the graduated release position, and valve means operated when a predetermined ratio is obtained between the pressures in said brake pipe and said source upon an increase in brake pipe pressure for reducing the operating pressure on said stop deviceA and on said equalizing valve device for moving said equalizing valve device to full release position.

ber supplied with fluid from said source, of. an equalizing valve device subject on one side to the pressure in said chamber and movable to a release position, upon a reduction in pressure in said chamber, for releasing the brakes, a spring, and valve means operative to effect a reduction in pressure in said chamber and subject to the pressure of the source on one side and brake pipe pressure plus the pressure of said spring on the opposite side.

16. In a fluid pressure brake, the combination with a brake pipe and a chamber, of an equalizing valve device movable to a graduated release position upon an increase in brake pipe pressure for releasing the brakes and movable to a full release position upon a reduction in pressure in said chamber for releasing the brakes, of a stop device operated upon a reduction in brake pipe pressure for temporarily preventing movement of said equalizing valve device from graduated release position to full release position, and means operative by brake pipe pressure for rendering said stop device ineffective and for reducing the pressure in said chamber.

17. In a fluid pressure brake, the combination with a brake pipe, a source of iiuid under pressure, and a chamber supplied with iiuid under pressure from said source, a choke for controlling said supply, an equalizing valve device movable to graduated release position upon an increase in brake pipe pressure over the pressure in said chamber for releasing the brakes and movable to full release position upon a reduction in pressure in said chamber below brake pipe pressure for releasing the brakes, a stop device having communication with said source of fluid under pressure and operated by iiuid under pressure from said source upon a reduction in pressure in said chamber for defining the graduated release position of said equalizing valve device, a choke in said communication, and valve means operated when the brake pipe pressure is increased to within a predetermined degree of the pressure in said source to vent fluid from said stop device for rendering same ineifective and to vent iiuid from said chamber.

18. In a iiuid pressure brake, the combination with a, brake pipe, a brake cylinder, and a choke, of valve means operative upon a reduction in brake pipe pressure to supply fluid under pressure through said choke to said brake cylinder, and a valve device operative upon a reduction in brake pipe pressure, by the pressure of iiuid supplied through said choke to said brake cylinder, to open a by-pass around said choke for increasing the rate of supply of fluid under pressure to said brake cylinder.

19. In a fluid pressure brake, the combination with a brake pipe and a brake cylinder, of valve means operated upon a reduction in brake pipe pressure to supply iiuid under pressure to said brake cylinder, a choke for restricting said supply in effecting a service application of the brakes, and a valve device operated upon anemergency reduction in brake pipe pressure to open a communication from said valve means to said brake cylinder around said choke.

20. In a iiuid pressure brake, the combination with a brake pipe and a brake cylinder, of valve means operated upon a reduction in brake pipe pressure to supply uid under pressure to said brake cylinder, a choke for restricting said Supply in yeffecting a service application of the brakes, and a valve device controlled by said valve means, and operative upon an emergency reduction in brake pipe pressure to open ,a by-pass around said choke for increasing the rate of supply of fluid under pressure from said valve means to said brake cylinder.

i 21. In a fluid pressure brake, the combination with a brake pipe and a brake cylinder, of valve means operated upon a. reduction in brake pipe pressure to supply uid imder pressure to said brake cylinder, a choke for restricting said supply in effecting a service application ofthe brakes, and a valve device controlled by said valve means and operative by the pressure of uid on the opposite sides of said choke upon an emergency reduction in brake pipe pressure to open a bypass around said choke for increasing the rate of supply of uid under pressure from said valve means to said brake cylinder.

22. In a uid pressure brake, the combination with a brake pipe and a brake cylinder, o! a choke for controlling the supply of iiuid under pressure to said brake cylinder in eiIecting a service application of the brakes, an emergency valve subject to the pressures on the opposite sides of said choke and operative to open a bypass around said choke for increasing the rate of` supply of iiuid under pressure to said 'brake cylinder in effecting an emergency application o! the brakes, an emergency piston operated by fluid under pressure to close said emergency valve, and valve means operated upon a reduction in brake pipe pressure to supply fluid under pressure to a communication leading to said choke and operative when the brake pipe pressure is vented at an emergency rate to vent fluid under pressure from said emergency piston.

23. In'a fluid pressure brake, the combination with a brake pipe and a brake cylinder., of a choke for controlling the supply of uid under pressure tc said brake cylinder in eecting a service application of the brakes, an emergency valve device normally subject to brake pipe pressure and operated upon a reduction in brake pipe pressure to open a by-pass around said choke for increasing the rate of supply of iluid under pressure to said brake cylider, a vent valve device normally subject to brake pipe pressure and operated upon a reduction in brake pipe pressure to vent fluid under pressure from said brake pipe to the atmosphere, and valve means operated upon a reduction in brake pipe pressure to supply fluid under pressure to said choke and to said by-pass and operated when the brake pipe pressure is reduced at an emergency rate to vent fluid under pressure from said emergency valve device and from said vent valve device.

24. In a uid pressure brake, the combination with a brake pipe and a chamber charged with fluid under pressure, of an equalizing valve device subject to the opposing pressures of the brake pipe and said chamber and movable to a release position for effecting a release of the brakes, and valvemeans operable separately from the equalizing valve device upon an increase in brake pipe pressure rfor venting fluid undery pressure from said chamber for effecting movement of said equalizing valve device to release position, said kequalizing Valve device controlling communication through whichruid is vented from said chamber. Y

25. In a fluid pressure brake, the combination with a brake pipe and a chamber charged with iiuid 'under pressure, oran equalizing valve die--d vice subject to the opposing pressures of the brake fluid under pressure, of an equalizing valve del vice subject to the opposing pressures of the brake pipe'and said chamber and movable to a release position for effecting a release of the brakes, a valve for venting iiuid under pressure from said chamber for effecting movement of said equalizing valve device to release position, and a movable abutment operable separately from the equalizing valve device upon an increase in brake pipe pressure for effecting the operation o! said communication through which fluid is vend from said chamber.

27. In a fluid pressure brake, the combination with a brake pipe and a chamber charged with iiuid under pressure, of an equalizing valve device subject to the opposing pressures o! the brake pipe and said chamber and movable to a release position for effecting a release of the brakes, a valve i'or venting fluid under pressure from said chamber for effecting movement of said equalizing valve deviceto release position, and a movable abutment subject on one side to a constant pressure and operated upon an increase in brake pipe pressure on the other side for effecting the operation of said valve, said equalizing valve. device controlling communication through which fluid is vented from said chamber by the operation of said valve.

28. In a fluid pressurebrake, the combination with a brake pipe and a chamber charged with uid under pressure, of an equalizing valve device having an application position :and a release position, avalve for venting uidgunder pressure'from said chamber for eiecting movement of said equalizing valve device to release position, and a movable abutment for operating said valve, said abutment having a chamber at one side adapted to be vented when the equalizing valve device is in application position and having a chamber at the opposite side, and means operatedupon an increase in brake pipe pressure for connecting said chamber at the opposite side to the brake pipe. Y 29. In a fluid pressure brake, the combination with a brake pipe anda chamber charged with fluid under pressure, of an equalizing valve device having an application position and.- a release position, a valve forventing fluid under pressure from said chamber for eiecting movement of said equalizing valve device to release position, and a movable abutment for operating' said valve, and valve means operated upon an increase in brake pipe pressure to supply iluid under pressure for operating said valve, said equalizing valve device being adapted in release position to close thek communication through which uid is vented from said chamber by operation of said valve.

30. In a fluid pressure brake, the combination with a brake pipe and a source of uid maintained at normal brake pipe pressure, of an equalizing --valve, said equalizing valve device controlling valve device subject to the opposing pressures of the brake pipe and a chamber and operated upon a reduction in brake pipe pressure to eiect an application of the brakes and movable upon a subsequent reduction in pressure in said chamber to a position in which the release of the brakes is effected, and valve means subject to the opposing pressures of said source and the brake pipe and operated upon an increase in brake pipe pressure for reducing the pressure in said chamber.

31. In a uid pressure-brake, the combination with a brake pipe, of an equalizing valve device subject to the opposing pressures of the brake pipe and a chamber and operated upon a reduction in brake pipe pressure to eiect an application of the brakes and movable upon a subsequent reduction in pressure in said chamber to a position in which the release of thei brakes is eiIected, a chamber charged with uid at a pressure which remains substantially constant, and valve means subject to the opposing pressures of the last mentioned chamber and said brake pipe and operlative upon an increase in brake pipe pressure to elect a reduction in the pressure in the rst mentioned chamber.

32. In a fluid pressure brake, the combination with a brake pipe, of an equalizing valve device subject to the opposing pressures of the brake pipe and a chamber and operated upon a reduction in brake pipe pressure to eil ect an application of the brakes and movable upon a subsequent reduction in pressure in said chamber to a position in whichv the release of the brakes is eiected, a chamber at all times chargedwith uid at the pressure normally carried in said brake pipe, valve means subject to the opposing pressures of the brake pipe and the last mentioned chamber and operative to effect a reduction in the pressure in the rst mentioned chamber, and pressure exerting means acting onsaid valve means and operative when a predetermined relation is obtained between the pressures in the last mentionedv chamber and the brake pipe, upon an increase in brake pipe pressure, for eiecting the operation of said valve means.

33. In a uid pressure brake, the combination with a brake pipe, of an equalizing valve device subject to the opposing pressures of the brake pipe and a chamber and operated upon a reduction in brake pipe pressure to effect an application of the brakes and movable upon a subsequent reduction in pressure in said chamber to a position in which the release of the brakes is effected, a chamber charged with `fluid .at a pressure which is independent of the pressure of uid in the rst mentioned chamber, valve means subject to the opposing pressures of the second mentioned chamber and the brake pipe and operative upon an increase in brake pipe pressure to reduce the pressure in the rst mentioned chamber, and means for controlling the time of operation of said valve means with respect to the pressures in the second mentioned chamber and in said brake pipe.

34. In a iiuid pressure brake, the combination with a brake pipe, of an equalizing'valve device subject to the opposing pressures of the brake pipe and a chamber and operated upon a reduction in brake pipe pressure to eiect an application of the brakes and movable upon a subsequent reduction in pressure in said chamber to a position in which the release oi the brakes is effected,

a chamber charged with fluid at a pressure whichis independent of the pressure of iiuid in the first mentioned chamber, valve means subject to the opposing pressures of the second mentioned chamber and the brake pipe and operative upon obtaining a predetermined differential between the last mentioned opposing pressures to reduce the pressure in the rst mentioned chamber, and means for defining said differential of pressures.

35. In a fluid pressure brake, the combination with a brake pipe, of an equalizing valve device subject to the opposing pressures of the brake pipe and a chamber and operated upon a reduction in brake pipe pressure to effect an application of the brakes and movable upon a subsequent reduction in pressure in said chamber to a position in which the release of the brakes is eiected, a chamber charged with iiuid at a pressure which is independent of the pressure of fluid in the rst mentioned chamber, valve means subject to the opposing pressures of the second mentioned chamber and the brake pipe and operative upon obtaining a predetermined diierential between the last mentioned opposing pressures to reduce the pressure in the first mentioned chamber, and a spring acting on said valve means for xing said dinerential of pressure.

36. In a uid pressure brake, the combination with a'brake pipe, of an equalzing valve device subject to the opposing pressures of the brake pipe and a chamber and operated upon a reduction in brake pipe pressure to effect an application of the brakes and movable upon a subsequent reduction in pressure in said chamber to a position in which the release of the brakes is eiected, a chamber charged with iiuid at a pressure which is independent of the pressure of iluid in the iirst mentioned chamber, valve means subject to the opposing pressures of the second mentioned chamber and the brake pipe and operative upon obtaining a predetermined diierential between the last mentioned opposing pressures to reduce the pressure in the first mentioned chamber, and a spring acting on said valve means for determining said diierential of pressures, and means for adjusting the pressure of said spring.

37. In a uid pressure brake, the combination .with a brake pipe, a source of uid maintained at a pressure equal to the normal brake pipe pressure and a chamber supplied with iiuid from said source, of lan equalizing valve device subject in one direction to the pressure in said chamber and movable to release position upon a reduction in pressure in said chamber for releasing the brakes, and valve means subject to the opposing pressures of the brake pipe and said source and operated upon anincrease in brake pipe pressure for reducing the pressure in'said chamber. y i

38. The combination with a brake pipe and a valve device controlled by the opposing pressures of the brake pipe and a chamber and operative upon a preponderance of brake pipe pressure over the pressure in said chamber to eiect a release of brakesjand valve means controlled by brake pipe pressure acting in opposition to a pressure substantially equal to that normally carried in said chamber and operated only when' the brake pipe pressure is increased to substantially the degree normally carried for eiecting a reduction in pressure in said chamber and thereby eiect said operation oi said valve device.

JOSEPH C. MCCUNE. 

